(1) Field of the Invention
The present invention relates to a system and a method for production of fabrics, and more specifically to textile machinery that can be directly fed threads or yarn wound on a beam.
(2) Description of the Related Art
In general, most textile machines that produce yarn wound it onto cones or small packages before it is further processed. For example, most fabrics with indigo dye are produced by yarn wound onto cones, dyed in indigo, and then wound on a beam (by a dye machinery), and then further processed through several steps to later be fed to knitting machines. The beam may be likened to a very large cotton reel, perhaps six feet long, having a large number of yarn threads (or ends) wound thereon in a generally parallel fashion. Of course, the yarns need not be dyed to be wound onto a beam. There are varieties of methods to produce indigo-dyed yarn, some of which are taught in U.S. Pat. Nos. 5,611,822 and 5,378,246, both to Gurley.
Regardless of whether a yarn is indigo-dyed or even dyed at all, most yarn wound onto a beam are however, unsuitable for use with certain knitting machines, including for example, both circular and flat bed knitting machines. The exceptions to this rule are the warp knitting machines, which can accept yarn directly from a beam.
The operation and use of warp knitting machines are different from both circular and the flat bed machines. In warp machines all components (feeders and needles) move synchronously and take in the same length of yarn ends from a beam simultaneously, creating uniform pattern fabrics. Although the synchronous movement of components allows yarn to be directly fed from a beam, it also limits the use of this machine to producing only certain types of fabrics. Hence, the warp machines are not as flexible and versatile as the circular knitting machines, and their use is limited.
The prior art circular or flat bed knitting machines cannot accept yarn fed from a beam because of the way they operate and therefore yarn must be fed to these machines by some other means. One known method is to use yarn wound onto individual cones or small packages, where it can later be fed from there to the knitting machine. In operation of these machines, needles having hooks at one end are moved in reciprocating fashion to engage yarns and to pull them into loops or various structures to form a knitted fabric. When circular or flat bed knitting machines proceed with knitting operations, yarn feeders (or guide feeders) feed the yarns continuously to the knitting needles. The needles then stitch or tuck the yarns to loops for forming the desired fabric. The feeders and the needles work independently. In fact, even the individual needles move independent of one another. Known positive feeding devices are sometimes used to help synchronize the movement of the needles with the yarn feeder operations. These devices help synchronize the speed with which all the individual yarn ends are pulled from cones with the operational movement (or pull) of each individual needle on the yarn. The positive feeding devices however, can only work with yarn fed directly from the cones or other small packages. They comprise of small rotating mechanisms, about three to four inches in diameter, and are moved by a belt system to xe2x80x9cpull-inxe2x80x9d the yarn.
The asynchronous movement of components within these machines makes them unsuitable for direct feeding of yarn from a beam. The reasons for this is because all individual yarn ends on a beam are uniformly wound and are let off (or unwound) uniformly. That is, the same yarn length for all yarn wound on a beam are uniformly let off for each degree of rotation of the beam regardless of the yarn length requirements of each individual feeder or needle in a knitting machine. In addition, a typical beam is about five feet in diameter, six feet in length, weighs hundreds of pounds, and has its own motor mechanism that rotates it independent of any other machine. This also makes it impossible for the prior art circular or flat bed knitting machine to xe2x80x9cpull-inxe2x80x9d yarn directly from a beam. Accordingly, the prior art circular or flat bed knitting machines must use yarn that was wound onto cones or other small packages.
The processing steps required to prepare these cones or the packages however, are tedious, very time consuming, labor intensive, and extremely costly. In addition, the quality of the yarn itself degrades after each of these processing steps, resulting in a poor quality knitted fabric. This is especially true for a dyed yarn in general and indigo-dyed yarns, in particular.
There are two main methods for winding yarns onto cones or packages, and they are taught by U.S. Pat. No. 4,613,336 to Quinnen and U.S. Pat. No. 6,199,787 to Jaffar et al. The entire disclosures of both of these patents are incorporated herein by reference. Quinnen moves each individual yarn end from a beam onto a plurality of cones. Jaffar et al transfers the individual yarn ends onto several skeins, and then back winds the yarn from each skein onto cones. A skein is a reel type structure that has one yarn end wound onto it. With both methods, the cones may then be manually placed onto creels for later use by circular or flat bed knitting machines. Creels are supporting devices that can hold several cones or small packages of yarn.
Several cones or skeins may be required to wind even a single yarn end from a beam because each beam may contain several thousand yarn ends, with each end approximately 50,000 to 60,000 yards. It will also take several skeins to back wind yarn onto a single cone.
As illustrated above, the steps taken by both methods are very involved and costly. In addition, these processes also reduce the quality of the dyed yarn due to abrasion. Abrasion is fundamental in the processing of most dyed yarns in general and indigo-dyed yarns in particular. Abrasion is the peeling or removal of dye surface material or dyestuff on a yarn. It occurs non-uniformly throughout the length of a dyed yarn with every step of yarn transfer. A dyed yarn wound on a cone may therefore have a darker color at its middle length and lighter at its two ends. When several cones having different degrees (or shades) of degraded dyed-yarn are used to knit fabrics, the final product produced may show undesired stripes or variations in color, sometimes known as barre lines. The transfer processes mentioned above also degrade the physical quality (e.g. texture, strength, etc.) of the yarn itself.
The cost associated with these processes are high because the yarn must be moved (or unwound) from a beam and then back wound onto cones (either directly or through skeins). The cones then must be manually placed onto creels, and the yarns on each cone hooked or connected physically to the knitting machines. The quality of the yarn also degrades with each transfer. These processes are also very labor intensive, requiring specialized personnel and equipment.
The present invention seeks to provide a system apparatus and methods for textile machines that can draw at least one yarn end (or thread) directly from at least one or more beams, reducing costs for specialized labor associated with yarn feeding processes.
The present invention further seeks to provide a system apparatus and methods for textile machines that draw at least one yarn end from at least one or more cones or small package structures to produce fabric with no barre lines.
The present invention also seeks to provide a system apparatus and methods for textile machines that draw at least one yarn end from at least one or more cones or small package structures and at least one or more beams simultaneously.
It is an object of the present invention to provide a system apparatus and methods that avoid abrasion problems associated with yarn transfers from beams or small packages to other small packages.
It is another object of the present invention to provide an appropriate method of yarn transfer from a beam to small packages, and from small packages to knitting machines in such a manner, that eliminates barre lines.
In keeping with the principles of the present invention, unique yarn feeding mechanism control systems and knitting machinery are presented which overcome the shortfalls of the prior art. The system comprises of at least one control unit having at least one central processing unit and sensory devices that enable synchronized feeding control of yarn from sources (beams, small packages, etc.) with the intake thereof of a plurality of knitting machines.
One or more control units output signals from one or more central processing units to beam rotating devices to control beam rotation and yarn feed to one or more knitting machine. The output signals are based on input signals from a variety of sensory systems located throughout the entire system. The variations in radius of each outer layer yarn end wound around beams, rotational speed of beams, movement and direction of compensators, and drive mechanism of knitting machines are all accounted for and synchronized by the control system to enable proper direct yarn feed from a plurality of sources to a plurality of knitting machines.